$python
>>> from dateutil.relativedelta import *
>>> import datetime
>>> one_month_ago = datetime.datetime.now() - relativedelta(months=1)
>>> one_month_ago
datetime.datetime(2013, 10, 18, 13, 47, 13, 110467)
>>> previous_month = one_month_ago.strftime("%B") 
>>> previous_month
'October'  
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